The paper presents the results of the systematic research into effects of 3d-metals acetates, acetylacetonates and double tartrategermanates/stannates on the modification of polyglycol maleine phthalate. The copolymerization parameters of the prepared modified oligoesters with methyl methacrylate monomer and threeethyleneglycoldimethacrylate oligomer were determined. Modifiers were added to the reaction mixture before the start of polycondensation of maleic and phthalic anhydrides with ethylene glycol at the temperature of 1750C. The kinetics of copolymerization at the initial stages was determined by the dilatometry at the temperatures of 500C to 600C. It was established that the modification of polyglycol maleinate phthalate with the studied compounds allows significantly increasing the rate and reducing the temperature coefficient of the copolymerization reaction. There advantages of the investigated double multi-metal mixed ligand coordination compounds as modifiers were proved as compared to the standard industrial systems, acetylacetonates and metal acetates. The presented modifiers are able to improve significantly the characteristics of the semi-finished products in the industrial manufacturing of copolymers without the significant change of the technological process.